Strokes Diary for the Winter (comments appreciated)

Discussion in 'Tennis Tips/Instruction' started by tonyplaystennisallday, Nov 14, 2013.

  1. tonyplaystennisallday

    tonyplaystennisallday New User

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    Ok, so I made an account pretty much because I have no idea what I'm doing in tennis anymore and thought I could use some advice. I'd like to post videos of my strokes over time and see if I can get some advice to get better especially in my groundstrokes before the Spring.

    Flat Serves:
    https://vimeo.com/79456917

    Topspin Serves:
    https://vimeo.com/79456916

    Strokes against a ball machine:
    https://vimeo.com/79457092

    Thanks for watching.
     
    #1
  2. LeeD

    LeeD Bionic Poster

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    Serves look better than groundies. But try to get the turn done during your prep, so you have less moving parts once you start the ball toss.
    Please set the ball machine for a lower, faster ball. Nobody hits moonballs to you all the time.
    Use a longer backswing both sides, to generate easy power, and less jerky swing. You can jump into the ball, but at this level, it's better to create power with a solid foundation and add the jumping once you make 4.5.
     
    #2
  3. tonyplaystennisallday

    tonyplaystennisallday New User

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    Here's a video of me hitting from today from the side. I have one from the back but the frame's a little crooked:

    https://vimeo.com/79530700
     
    #3
  4. WildVolley

    WildVolley Legend

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    Serves don't look bad. Could you shoot them in slow motion? That would allow a little better analysis of what is happening.

    You have good shoulder turn and a good shoulder angle leading into the serve and at trophy, but somehow you're losing power between trophy and contact. I'm not the best at doing analysis with full speed video, but it seems that your drop is not very deep and something is disconnected in your kinetic chain.

    I'll look at some of the other videos when I have more time. Good luck and keep practicing.
     
    #4
  5. BIGJ98

    BIGJ98 Rookie

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    On your groundstrokes bend your knees right before contact. This will get the drive from your legs and produce more power.
     
    #5
  6. Chas Tennis

    Chas Tennis Hall of Fame

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    Your camera has a fast shutter that shows the position of the racket. It is difficult to catch the more interesting frames, such as impact, because the frame rate is slow. Was it 30 fps? (I just learned that if you upload a 60 fps video to Vimeo the file will be processed to 30 fps by discarding every other frame.)

    Caught this frame as the first flat serve. Sec 4 or 5.

    [​IMG]

    It looks as if the racket is still pointing back toward the camera - not sure how close that frame is to impact.

    Your arm looks straight and is probably rotating from internal shoulder rotation (mislabeled pronation) but that can't be seen with just this one frame rate. The line between your two shoulders and your upper arm looks a little lower than usual. Compare to the slightly higher angle in the picture of a kick serve below which is at impact. Your upper arm is at slightly downward angle and his slightly up. See that? See the Ellenbecker video for the shoulder-upper arm angle. Your spine looks a little too horizontal but I need equivalent viewing angles to compare better. See if you can find that body angle in a high level serve. A camera angle where the camera looks along the ball's flight path and catches impact is sometimes very useful to compare to the pros serves. See frame below.

    [​IMG]

    Have posted in many recent serve threads. Search this forum: Camera behind Chas Tennis OR Serve ISR Chas Tennis etc to find the threads.

    The Ellenbecker 20 minute video discusses the shoulder and the orientation to use to reduce the risk of impingement. In that frame, you seem to be doing it a little more than usual or necessary. Search (above search box) this forum with "Show Posts": Ellenbecker
    A high speed video camera is necessary to see what you are doing on the serve. Your camera is very good for catching a few sharp frames but only at random times during the serve. If interested in a cheap high speed video camera.
    http://tt.tennis-warehouse.com/showpost.php?p=7741038&postcount=47
     
    Last edited: Nov 15, 2013
    #6
  7. LeeD

    LeeD Bionic Poster

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    Groundies...
    You've got an educated swing, but it's waaaaaaaaay too short, so you don't generate any power. Take a backswing, then swing forwards with your elbows more away from your torso, to increase lever arm.
    Stand with feet apart, like an athlete.
    Stand 3' behind the baseline, set the machine or tell your buddy to hit deeper shots to you.
    There is NO practice from NML no man's land that is useful to you right now.
    Meaning, you're too good to be hitting from NML.
     
    #7
  8. WildVolley

    WildVolley Legend

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    Watched a little of the groundies video. To back up Lee, you need more of a unit turn, which means more hip and shoulder turn. From what I saw, you are basically staying in an open stance with a very short-backswing, which doesn't allow you to take a proper cut at the ball.

    Make sure that you get a full unit turn, which means that your shoulders should turn until they are at least perpendicular with the net. This will give you more power and a longer swing.
     
    #8
  9. tonyplaystennisallday

    tonyplaystennisallday New User

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    Alright, so I went out today keeping in mind to have a fuller unit turn on the groundstrokes and on the serve to, per se, impinge more. I had read about impinging before and maybe I was overcompensating for it by having the angle of my shoulders off by too much. In the video from today, the angle is from behind. The courts are a little wet from rain, but it didn't affect me too much. I serve starting around 2:45. The first 6 serves are flat and the rest are topspin. My groundstrokes seem better but it's like nothing I've ever done before and I'm pretty wildly inconsistent. My serve has much better direction.

    https://www.youtube.com/watch?v=QQrNQY-jdhA
     
    #9
  10. tonyplaystennisallday

    tonyplaystennisallday New User

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    Also, I'll see what I can do about a high speed camera. It sure seems like a good idea.
     
    #10
  11. Chas Tennis

    Chas Tennis Hall of Fame

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    On Youtube I am having trouble stopping the video nearest impact. Youtube and Vimeo do not do single frame very well. You should be able to do that using your computer on the original video. Quicktime works very well for single frame stop action. QT may already be on your computer or download free Quicktime from the Apple site or Download.com. I have not used the MS video player on my videos very much so I'm not sure how well it does single frame forward and backward. MS movie player most likely came loaded on your computer (the default movie player). Try it. Any problems with single frame use Quicktime.

    Also, your camera was aligned with the court centerline. I use the camera aligned with the likely flight of the ball. Video either the add court serves or deuce court serves for several serves. Then move the camera for the other side. In the overcast sky your camera still has a fast shutter and small motion blur.

    What camera are you using? Some will do 60 fps at 720 lines but only 30 fps at 1080p lines.

    "on the serve to, per se, impinge more." I don't understand this wording. Have you watched the Ellenbecker video? The idea is to use an orientation for the shoulders to minimize shoulder impingement and the risk of shoulder injury from the impingement.

    Google: pictures shoulder impingement

    Look at the first video on impingement, 2011 Flouroscope.....
    http://www.kirschshoulder.com/Kirsch_Shoulder/Shoulder_Imaging/Shoulder_Imaging.html

    The videos on my Vimeo site show what high level servers are doing. (Ignore the club player serves.) I'd say most have the upper arm go upward a small angle relative to the line between the shoulders. (10-20° ?) An exception might be the Roger Federer serve that has the largest angle up for the upper arm relative to the shoulders. He had a back injury at that time and that may account for it or maybe he uses more than most. ?

    Your head seems to be at more of a right angle to your shoulders. ? Camera angle? I'm not sure and need to look at the videos more. Compare some of your videos nearest impact to the pros at impact. Wawrinka probably keeps his head closer to the shoulder than most - compare that feature and others also. I'd say they have their heads closer to the hitting shoulder with the one shoulder low and the hitting shoulder high orientation. See the Ellenbecker video on the shoulder orientation.

    Of the pro servers, the serve shown in reply #6 has the head the most perpendicular to the shoulders and his upper arm very slightly up. His head might be similar to yours, his upper arm slightly up. ?

    More typical of pro servers, Raonic serve. Head orientation and upper arm orientation. Compare to yours.
    https://vimeo.com/66720474

    Raonic serve from another video. Notice also the overall line from his foot to his wrist from this camera angle. From the side it looks different. Compare to your overall line when you catch an impact from behind with camera on the ball's flight path.
    [​IMG]

    I'd suggest that you do much less practicing and more careful comparing of a few of your captured frames at impact to those on my site and similar high level serve videos. Best camera view along the ball's flight path from front (as Raonic frame) or from behind.

    Keep in mind that your camera only catches one frame every 33 millisecond if 30 fps. The last forward acceleration of the racket to impact takes about 20 milliseconds total. [A tenth of a second is 100 milliseconds.] Catching impact, which lasts about 2-4 milliseconds, is rare at 30 fps. Might catch close to impact 20% of the serves. The neck and shoulder angles change slowly and last for some time around impact. But the racket-forearm angle changes very rapidly and it is hard to tell when you catch an impact frame unless the ball is compressed on the strings. Same for the angle of the rotating string face around impact - almost no information on slice, kick or flat serve impact variations with 30 fps.
     
    Last edited: Nov 18, 2013
    #11
  12. tonyplaystennisallday

    tonyplaystennisallday New User

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    Another strokes video, from the side and back:

    https://www.youtube.com/watch?v=ufjkNHu8Smk&feature=youtu.be


    I'll try to get some better angles of my serve for now (hopefully tomorrow if the weather isn't bad) and look more at the angles of my arm and head like you're saying so maybe we can get on the same page.
     
    #12
  13. LeeD

    LeeD Bionic Poster

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    Watched you last two vids.
    Strokes too short, not enough takeback, very little power BUT, very trained and your hand knows what it's doing, it just doesn't do much.
    And no footwork. Never stand with feet together, as you don't have balance or movement once the points count.
    Try harder. Pretend you're playing a sport.
     
    #13
  14. kvan

    kvan Rookie

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    Consciously split step if you don't have that in your system yet, and bend your knees!
     
    #14
  15. tonyplaystennisallday

    tonyplaystennisallday New User

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    More strokes. Here I really tried to focus on getting lower and having a longer stroke, but when I look at it it doesn't look much different than before. Am I wrong?

    Oh, and I'll try to get a better serve video if I ever see the sun again, :( .

    https://vimeo.com/80097059
     
    #15
  16. LeeD

    LeeD Bionic Poster

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    Not much diff....
    You should try some self drop feeds. Hit them HARD, like you're playing against a good player. That dead ball power is lacking in your strokes, because your stroke is short and stunted.
    You need to lengthen your backswing on slow incoming balls, then use YOUR short takeback method on hard hit deeper balls.
     
    #16
  17. Chas Tennis

    Chas Tennis Hall of Fame

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    Here are some Tennisoxygen videos with detailed analyses of strokes.
    http://www.youtube.com/user/xstf/videos

    Compare your forehands to these. Looks as if your take back might be less of a body-hip-shoulder turn than these. More arm and less body? How does your arm motion compare to theirs? How does your body rotation compare to theirs? How high are their rackets on the take back? How high is your? ..............

    Strokes all utilize some stretch-shortening cycle for several body parts. Do you see the SSC when it occurs in the pro videos?

    Rick Macci has some excellent videos including some new ones.

     
    Last edited: Nov 22, 2013
    #17
  18. tonyplaystennisallday

    tonyplaystennisallday New User

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    #18
  19. LeeD

    LeeD Bionic Poster

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    Still, no backswing, not enough anyways, and your bent elbow is costing you power.
     
    #19
  20. tonyplaystennisallday

    tonyplaystennisallday New User

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    So far I've just been trying small adjustments to get a better unit turn and more power. Next time I hit, should I just try to change my stroke completely and turn, bend my knees, and straighten my arm as much as I can? Even if it means most of my balls will probably go out?
     
    #20
  21. WildVolley

    WildVolley Legend

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    That might be a good idea. You're one of the few guys here who posts video who has too little body turn. You might want to do what you find exaggerated in terms of turning in order to get more of a feel for it.

    Since you're already using video. I'd try to find some good video of a pro hitting to use as a model. Then copy that form until you look the same. Don't worry as much about where the ball is going. Just work on form for a little bit.
     
    #21
  22. tonyplaystennisallday

    tonyplaystennisallday New User

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    [​IMG]

    Alright, as for my serve here is a picture of me at contact and Federer right before contact. I can tell that my body is more chaotic, my spine more horizontal, and the angle between my arm and body more obtuse than Federer's. How would I go about correcting this? Is this a problem in my toss, footwork, etc? Or do I just need to try and force myself to straighten up before I hit the ball? I'm going to go out today and record my serve again and more groundstrokes to see if there's improvement.

    Also, here's the video of my serves:

    https://www.youtube.com/watch?v=Sob6xH_WY78&feature=youtu.be
     
    #22
  23. Chas Tennis

    Chas Tennis Hall of Fame

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    The racket changes position very rapidly around impact. You probably don't have impact in your picture (?)which I can only identify by the squishing of the ball. With 240 fps you usually get one frame with impact every serve. With 30 fps not many impacts. How can you tell if it's just before or after impact? Check the fall path and the first ball after impact will have moved from the fall path. You should be looking at your video files using Quicktime or Kinovea for solid single frame advance. 30 fps and Youtube stop action is cumbersome and may lead to mis-interpretations because of the 30 fps framing rate.

    Your spine has too large a bend and is too horizontal because you developed your own serving motion. No forcing. Difficult to change muscle memory. You can easily see these things as you found.

    I see the Canon Powershot 110 HS refurbished for $104, free shipping.
    http://shop.usa.canon.com/shop/en/catalog/powershot-elph-110-hs-red-refurbished
    In bright sunlight, that basic camera can show you the fastest motions in the serve. I tested this camera for motion blur.

    For the fastest motions of the serve 30 fps is a waste of time, or worse if it misleads you.
     
    Last edited: Dec 4, 2013
    #23
  24. tonyplaystennisallday

    tonyplaystennisallday New User

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    #24
  25. Topspin Shot

    Topspin Shot Legend

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    What the heck are you doing? Stop right now!!! Seriously, stop taking advice from TT right now and go find a real coach if you want to improve your game. In the meantime, go back to your old way of hitting because that was light years better than what you're doing in this video. I'm really disappointed in TT right now. This is as bad as the pronation guy who came on a couple weeks ago. Tony, this is not your fault, but this is what happens when rec hacks (I will say that not everyone who's posted on this thread is giving bad advice, but many are) try to give you advice and you don't realize that they are in fact rec hacks. I'm really ashamed of this forum right now.
     
    Last edited: Dec 2, 2013
    #25
  26. Chas Tennis

    Chas Tennis Hall of Fame

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    Which earlier way of hitting are you referring to, which video? What is the difference?
     
    #26
  27. Topspin Shot

    Topspin Shot Legend

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    I'm referring to how he looked in the video included in his original post. He's now crouching down lower than an infielder fielding a ground ball, moving in a waddling fashion because his legs are so far apart, and slapping at the ball with a ridiculously shaped backswing. He's also missing a very large number of his shots because of the ridiculous form.
     
    #27
  28. jhick

    jhick Semi-Pro

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    IMO, not necessarily fair take it out on forum posters. No one told the guy to crouch down and start swinging wildly.
     
    #28
  29. WildVolley

    WildVolley Legend

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    And you think someone in this thread told him to do that?:confused:

    I think that he misinterpreted my advice or I didn't take him at face value. The exaggerated crouch is obviously silly, but the greater turn of his shoulder is an improvement as compared to the earlier videos in which he didn't have much of any shoulder turn and just slapped at the ball from a forward facing open stance.

    Tony, please get rid of the exaggerated crouch. Bending the knees is good, but an extreme bend for show isn't going to help.

    The shoulder turn was an improvement, though your kinetic chain still needs a little work.
     
    Last edited: Dec 2, 2013
    #29
  30. Topspin Shot

    Topspin Shot Legend

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    People kept insisting he bend his knees and take a bigger backswing. What do you expect him to do other than bend into a squat/split and enlarge his backswing without changing its shape? I'm not calling anyone out in particular because no one poster is at fault, but this is the nature of the beast when crowdsourcing goes wrong. It's really frustrating to see another well intentioned player make his form worse by listening to TT posters.
     
    Last edited: Dec 2, 2013
    #30
  31. WildVolley

    WildVolley Legend

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    At the very least, his shoulder turn is superior to that in the original video.:)

    Watch the first video. Notice how he barely has a hint of a unit turn and now he's almost doing a good natural unit turn, though the rest of his swing is wild.

    I think he needs to spend some time in front of a mirror modeling a good stroke and then work against slower paced balls.

    Watching the videos again, I don't see that the new stroke is noticeably worse than the original.
     
    #31
  32. shindemac

    shindemac Hall of Fame

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    Way too exaggerated. If you're goona swing so wily , better to shadow swing .
     
    #32
  33. Chas Tennis

    Chas Tennis Hall of Fame

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    Serve Model - Pete Sampras

    One of the better videos for finding checkpoints from a very high level serve.
    Not sure what type of serve this is.

    I noticed in your side-by-side serve pictures with Federer that your body had a considerably different degree of turn. However, that could be the time that those frames were caught especially with the 30 fps frame rate. Federer is before contact. You might be after contact........ Better to compare impacts with the ball clearly on the strings and the same type serves. I usually can't be very confident of the type of serve unless I see the ball trajectory curve and also the bounce.
     
    Last edited: Dec 3, 2013
    #33
  34. tonyplaystennisallday

    tonyplaystennisallday New User

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    Well I thought my strokes were pretty silly; I didn't think they were this laughable. Anyway, I went out today and here are some better groundies: (Also, I'll try to get a high speed camera in the coming weeks)

    Groundies:
    https://vimeo.com/80926760
     
    #34
  35. Topspin Shot

    Topspin Shot Legend

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    ^^^That's better. A little knee bend and shoulder turn is good, but too much is too much. Now, if I were your coach, the first thing I would teach you to stop many of the errors is to keep the plane of your racket the same through the hitting zone. This video tells all. http://m.youtube.com/watch?v=5ot2xQJRJ5Q&desktop_uri=/watch?v=5ot2xQJRJ5Q

    P.S. Ignore Topslice. He's a troll who pretends to be a coach. He insults everyone's game.
     
    #35
  36. tonyplaystennisallday

    tonyplaystennisallday New User

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    #36
  37. Topslice

    Topslice Guest

    You had to of been messing in your earlier video. It was so bad it was like you purposefully hit with the most ridiculous technique to troll us.

    The forehand is awesome now, top notch, cant belive it is so much better.
     
    #37
  38. WildVolley

    WildVolley Legend

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    Much better form. You've got a decent unit turn on the fh - nice.

    Sometimes you are not consistently spacing yourself with respect to the ball, so be willing to move your feet. The swing is looking more natural. To make it more consistent, try to lock your arm into position at the end of the pat-the-dog portion of your backswing.

    You're definitely showing improvement. Keep up the practice.
     
    #38
  39. Chas Tennis

    Chas Tennis Hall of Fame

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    This is the final acceleration of the racket head leading to impact. Notice everything that is accelerating in these frames. (there are some camera viewing angle issues..ignore them) What is making the racket speed up?

     
    Last edited: Dec 4, 2013
    #39
  40. tonyplaystennisallday

    tonyplaystennisallday New User

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    #40
  41. tonyplaystennisallday

    tonyplaystennisallday New User

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    Also this is my first day trying the camera, so I'll try to go out and get some better pictures when the light is better on another day.
     
    #41
  42. Chas Tennis

    Chas Tennis Hall of Fame

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    What camera? Fixed wide angle lens? Frame rate?

    Next time try some with a larger image. Cover from below the feet to above the racket, maybe 10% of the frame above and below. Try close up of just the upper half of your body.

    Best motion blur probably will result with bright sunlight and the widest angle setting for a zoom lens. The camera has automatic exposure control (AEC) and sunlight and the wide angle cause the AEC to select the fastest shutter.

    I have a large, clunky, Polaroid 72" tripod. $40. I like it because it was cheap, goes to 71" and has a geared elevator that is sometimes very useful (elevate to look through a fence, etc.). I also have a cheap $15 tripod that is very small but only goes to 49". 49" is fine for ground strokes but the higher the better for serves. You can safely place the tripod many places on your court when practicing serve provided there are no balls from other courts. I would not place a tripod behind the player inside the fence for ground strokes. I'd shoot ground strokes through the fence or from the side.
     
    Last edited: Mar 28, 2014
    #42
  43. tonyplaystennisallday

    tonyplaystennisallday New User

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    Canon Powershot EPLS 110 HS, 120 fps at 640 x 480. I know computers but not cameras well. Here are the rest of the specs: http://www.usa.canon.com/cusa/suppo...d_series/powershot_elph_110_hs#Specifications

    And I wished I could've gotten the view closer to me but I could only support the camera on a fence. I suppose I could get it on my big bag or something and bring it a little closer but it wouldn't be as high. Should I really invest in a tripod?
     
    #43
  44. Chas Tennis

    Chas Tennis Hall of Fame

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    That is the camera that I tested.

    To get minimum motion blur
    1) use the widest angle zoom setting of the camera
    2) shoot in direct sunlight (shadows will appear in the video)

    I only shot at 240 fps. The motion blur allows the location of everything to be seen. From behind things do not move quite as fast so the side view shown here is a better test for motion blur. I did not test from the behind view. The video on my computer using Quicktime looks better that this picture. The QT stop action works very well using the arrow keys.

    [​IMG]

    [​IMG]
     
    Last edited: Mar 28, 2014
    #44
  45. tonyplaystennisallday

    tonyplaystennisallday New User

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    Should I only shoot in 240 fps? On this camera the resolution goes down quite a bit from shooting in 120 fps. I'll try to get closer and more sunlight tomorrow.
     
    #45
  46. Chas Tennis

    Chas Tennis Hall of Fame

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    240 fps vs 120 fps

    It is important to see the phase of your serve leading to ball impact. What happens just before impact determines your serve. The final approach to the ball is very fast for a high level serve, it takes only about 25-30 milliseconds.

    Playback at 30 fps. Recorded at 240 and played back at 30 fps, the actual 30 milliseconds is displayed for only 1/4 second. It is very easy to miss this 1/4 second - final racket acceleration toward the ball - during regular playback at 30 fps.

    240 vs 120 fps. At 240 fps the camera records a frame every 4.2 milliseconds. In 30 milliseconds, it records only 7 frames. 240 fps usually catches the ball while in contact with the strings because it takes a frame every 4.2 milliseconds and the ball is in contact with the strings for about 3-5 milliseconds. At 120 fps the camera records a frame every 8.4 milliseconds and catches only 3 frames in 30 milliseconds.

    See Fastest First then Work Back. It is a good approach to first understand the fastest part of your serve. 240 fps is excellent for that. Then later decide the recording frame rate for seeing whatever you want to see.

    Your camera has two very useful features:

    1) a 30 second trigger delay - press start button and video starts 30 seconds later.

    2) editing to get rid of dead wood video

    Focus. I usually focus by pointing the camera down at the lines on the court at the right distance and pressing the still trigger button down half way to focus the camera. With very low resolution focus has less impact. If court lines are in the frame I can sometimes see how well tha camera was focused by looking at the lines as they extend away. Where was the best focus?
     
    Last edited: Mar 30, 2014
    #46
  47. Avles

    Avles Hall of Fame

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    I have your camera (or did, until I managed to get soapy water in the mechanism) and I don't see a real advantage from 240 fps-- it makes things pretty grainy and the extra frames don't tell you much.

    HS video is fun to play with and maybe can tell you some things, but you may find that going frame by frame in 30 fps video (which you can do with most media players I think) is almost as revealing. I think most of the problems players at our level encounter are clear enough to see at 30 fps.
     
    #47
  48. Chas Tennis

    Chas Tennis Hall of Fame

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    1) Cameras with telescoping lens tubes can have problems getting sand or dirt in the telescoping lens tubes. There are Youtube videos on cleaning the lens tubes. Keep the camera clean.

    2) There have been some problems also where a 'lens error' occurs, in one case because a connector came lose inside the camera. That problem was acknowledged for one Powershot, the model S100.
    http://www.usa.canon.com/cusa/support/consumer?pageKeyCode=prdAdvDetail&docId=0901e024805ab992

    3) If the camera is not working because the electronics got wet, they generally recommend trying to dry out electronics in rice or other desiccant. Google similar techniques.
    http://lifehacker.com/269427/dry-out-your-soaked-gadgets-in-rice/all

    Careful not to get dust, dirt, rice or desiccant debris into the lens tubes.

    Try asking in a photographic forum such as dpreview.
    http://www.dpreview.com/forums/1018
    http://www.dpreview.com/forums/1010..._source=mainmenu&utm_medium=text&ref=mainmenu

    I dropped my 110 HS a few feet onto concrete. Tiny dings on two corners but it still worked OK. Always wear the wrist strap when the camera is out of its case.
     
    Last edited: Mar 30, 2014
    #48
  49. tonyplaystennisallday

    tonyplaystennisallday New User

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    #49
  50. LeeD

    LeeD Bionic Poster

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    I'd recommend working on some recovery after serving. Right now, you are walking to your left, facing the left. Your opponents would be good players who can hit wide to your forehand.
    Lotsa Almagro here on the serves.
     
    #50

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